Many different diseases may result in vision loss and even blindness, if not promptly recognized and treated. Vision loss associated with retinal diseases typically involves several important symptoms including image distortion, decrease in visual acuity, loss of contrast discrimination, especially in low lighting conditions, holes or defects in the visual field, or inability to accurately distinguish colors.
Severity of symptoms is typically highly correlated with the stage of the disease, and generally, earlier diagnosis and treatment improve the potential for a good outcome. Important changes in the visual function can be quantified by the vision tests, which have been historically administered in the offices of eye physicians and optometrists.
Availability of new tools for the treatment of retinal diseases, particularly a class of compounds called VEGF inhibitors (Lucentis and Avastin) have dramatically improved the therapeutic outcomes. However, every patient is different with respect to the optimum dose and frequency of these treatments. Without frequent measurements of vision to monitor disease progression some patients may be under-treated, while others over-treated. Under-treatment can lead to severe and irreversible disease progression and associated loss of vision. Over-treatment is expensive, uncomfortable and potentially increases the risk of complications.
A single test in the doctor's office provides only one snapshot of the visual function, and may be a subject to random fluctuation of vision. Frequent testing of vision using a variety of tests will allow detecting trends in the visual function with much higher precision than a single test can provide. As a result, there is a need in the art for improved analysis of visual function.